IETF Logo Mail Archive

SCTP-over-UDP and port 9899

"Dan Wing" <dwing@cisco.com> Mon, 31 October 2011 20:11 UTC

Return-Path: <dwing@cisco.com>
X-Original-To: tsvwg@ietfa.amsl.com
Delivered-To: tsvwg@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id EF87321F8DDF for <tsvwg@ietfa.amsl.com>; Mon, 31 Oct 2011 13:11:05 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -105.514
X-Spam-Level:
X-Spam-Status: No, score=-105.514 tagged_above=-999 required=5 tests=[AWL=1.085, BAYES_00=-2.599, RCVD_IN_DNSWL_MED=-4, USER_IN_WHITELIST=-100]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id N2lUDl1L5LZD for <tsvwg@ietfa.amsl.com>; Mon, 31 Oct 2011 13:11:04 -0700 (PDT)
Received: from mtv-iport-2.cisco.com (mtv-iport-2.cisco.com [173.36.130.13]) by ietfa.amsl.com (Postfix) with ESMTP id C8ED321F8DDD for <tsvwg@ietf.org>; Mon, 31 Oct 2011 13:10:57 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=dwing@cisco.com; l=720; q=dns/txt; s=iport; t=1320091858; x=1321301458; h=from:to:subject:date:message-id:mime-version: content-transfer-encoding; bh=WJm/HFzKf7tuJGqVyaVrXWCTrHSSQdW/jzeEK0v6P8I=; b=AP5H4TgpakFIx89+bKwP5fBDTmbrC64eE9FUd1lrjgWJ/VvWviQetBCT e/XNIy16T/YvQskVdKllUDtLIhu8Y1qrtftfH1SjZJcaMQZaejolJpmY/ yUkrTWduX4YDPd/bgh4Pupd7yEF9Ae/hTYos3Race8BUom+VOzeZDjCBo w=;
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: AhAFALoAr06rRDoI/2dsb2JhbABEm06NaIEFgXkICgEXEEwFGFAjHAEEAR0Xh2iVUAGeP4kCBIgGngc
X-IronPort-AV: E=Sophos;i="4.69,434,1315180800"; d="scan'208";a="11490730"
Received: from mtv-core-3.cisco.com ([171.68.58.8]) by mtv-iport-2.cisco.com with ESMTP; 31 Oct 2011 20:10:50 +0000
Received: from dwingWS ([10.32.240.195]) by mtv-core-3.cisco.com (8.14.3/8.14.3) with ESMTP id p9VKAoXP011603; Mon, 31 Oct 2011 20:10:50 GMT
From: Dan Wing <dwing@cisco.com>
To: tsvwg@ietf.org, 'Michael Tuexen' <tuexen@fh-muenster.de>, randall@lakerest.net
Subject: SCTP-over-UDP and port 9899
Date: Mon, 31 Oct 2011 13:10:51 -0700
Message-ID: <193601cc9809$2ffa6b50$8fef41f0$@com>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
X-Mailer: Microsoft Office Outlook 12.0
Thread-Index: AcyYCS+hu+pmIlMsTRy0MExRcxu1Lw==
Content-Language: en-us
X-BeenThere: tsvwg@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Transport Area Working Group <tsvwg.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/tsvwg>, <mailto:tsvwg-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/tsvwg>
List-Post: <mailto:tsvwg@ietf.org>
List-Help: <mailto:tsvwg-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/tsvwg>, <mailto:tsvwg-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 31 Oct 2011 20:11:06 -0000

http://tools.ietf.org/html/draft-ietf-tsvwg-sctp-udp-encaps-01 and its
predecessor both say:

  "When inserting the UDP header, the source port is 9899, the
   destination port is the one stored for the destination address the
   packet is sent to or 9899 if no destination address is stored."

Why is it important to use a specific source port?  Does that not
cause difficulties if there are two (or more) instances of SCTP-
over-UDP applications running on the same host?  Does that not
cause difficulties, in implementation assumptions, if there are
two hosts behind the same NAPT and only one can get UDP/9899 
forwarded to them?

In short, what is the benefit of using 9899 as the source port?

-d

v2.46.0 | Report a Bug | By Email | System Status